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Abstract  

Characterization of SuperLig® 620 solid phase extraction resin was performed in order to develop an automated on-line process monitor for 90Sr. The main focus was on strontium separation from barium, with the goal of developing an automated separation process for 90Sr in high-level wastes. High-level waste contains significant 137Cs activity, of which 137mBa is of great concern as an interference to the quantification of strontium. In addition barium, yttrium and plutonium were studied as potential interferences to strontium uptake and detection. A number of complexants were studied in a series of batch Kd experiments, as SuperLig® 620 was not previously known to elute strontium in typical mineral acids. The optimal separation was found using a 2 M nitric acid load solution with a strontium elution step of ~0.49 M ammonium citrate and a barium elution step of ~1.8 M ammonium citrate. 90Sr quantification of Hanford high-level tank waste was performed on a sequential injection analysis microfluidics system coupled to a flow-cell detector. The results of the on-line procedure are compared to standard radiochemical techniques in this paper.

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-6031(97)00370-5 . 11. von Stockar , U Duboc , P , Menoud , L , Marison , IW 1997 On-line calorimetry as a technique for process monitoring and control in biotechnology . Thermochim Acta 300 1–2 225 – 236

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Abstract  

In chemical processing technology on-line activation methods gain an increasing importance for process monitoring and control. In the paper presented a method is described according to which the different fluorspar contents at various strategic points of a flotation plant are to be determined through neutron activation by 100 μg252 californium. For that purpose, a continuous analytical system for on-stream process control of slurries was designed and constructed. This SUSAC compact facility allows continuous application of the method on an industrial scale.

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Abstract

In this study, we developed the technique of Li+ ion-attachment mass spectrometry (IAMS), a method that has shown promise in the fields of chemical analysis, plasma diagnostics, chemical process monitoring, and thermal analysis. The experimental setup is such that Li+ ions get attached to chemical species (R) by means of intermolecular association reactions to produce (R + Li)+ adduct ions, which are then transferred to a quadrupole mass spectrometer. Recently, an IAMS system became available commercially in a complete form from the Canon Anelva Corp. IAMS has several notable features. It provides only molecular ions, and it permits direct determination of unstable, intermediary, and/or reactive species. Also, it is highly sensitive because it involves ion-molecule reactions. With regard to its applications for thermal analysis, one of its greatest advantages is that it can be used to directly analyze gaseous compounds because it provides mass spectra only of the molecular ions formed by Li+ ion attachment to any chemical species introduced into the spectrometer, including free radicals. Coupled with evolved gas analysis, IAMS works well for the analysis of nonvolatile, untreated, and complex samples because the simplicity of the ion-attachment spectrum permits the analysis of mixtures electron-impact spectra of which are difficult to interpret.

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Abstract  

One of the most critical elements of a performance evaluation (PE) program for radioactivity measurements is the traceability of the PE materials to the national standards. The requirements and criteria for the production of traceable environmental and radiobioassay PE materials have been defined by ANSI N42.22 and ANSI N13.30 standards. It is important to note that use of traceable source materials does not necessarily ensure the traceability of subsequently derived PE materials unless verification measurements exist in conjunction with the preparation processes. This paper describes the protocol currently used by NIST for the preparation and verification of air filter, acidified water, spiked soil, synthetic urine, and synthetic fecal PE materials for low-level radioactivity measurements. The process involves gravimetric dilutions and mixing of primary radionuclide NIST Standard Reference Materials (SRMs), addition of the derived master solution to sample matrices, and subsequent verification measurements. Several gamma-emitters were used to trace the gravimetric dilutions and spike addition through an unbroken chain of gamma comparison measurements. The massic activities of alpha- and beta-emitters in the diluted solutions and PE samples were also measured by radiochemical methods and compared with their gravimetric values. A correlation analysis demonstrated that the gamma emitters quantitatively followed 90Sr, 238U, 238Pu, and 241Am throughout the dilution and spiking and can be used as effective process monitors. The statistical results from t-tests, box plots, and normal probability tests suggested that traceability of radionuclides in the PE materials to their primary standards can be verified to within 1%, with an overall precision better than 2% (1s).

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Journal of Flow Chemistry
Authors: Olav Bleie, Michael F. Roberto, Thomas I. Dearing, Charles W. Branham, Olav M. Kvalheim, and Brian J. Marquardt

The Moffatt-Swern oxidation (MSO) is a multistep, versatile, metal-free reaction by which alcohols are transformed into aldehydes and ketones. Batch MSO requires low temperatures (−70 °C) due to a highly exothermic reaction step that generates intermediates. This work shows that a rigorous investigation of the MSO in batch can be used as a stepping-stone to its implementation in a continuous-flow reactor (CFR). This work has two parts: the first part details the investigation of MSO in batch; the second covers the translation of the knowledge derived from batch to a CFR. The MSO batch reaction was performed under cryogenic conditions with real-time process monitoring. The reaction was monitored with Raman spectroscopy and could be tracked throughout the reaction. All concentrations were validated using offline high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). Two configurations of the CFR were produced. Configuration 1 used the traditional batch methodology in terms of reagent addition and reaction conditions. Configuration 2 used the information derived from the batch reaction, changing the order of the reagent addition and increasing the temperature of the reactor. Real-time quantitative monitoring of chemical yield in the CFR was demonstrated via Raman spectroscopy and partial least squares (PLS) regression modeling. Reaction yield was accurately predicted every 15 s, reducing the need for chromatographic validation once the model was built. Configuration 2 was shown to perform comparably to configuration 1 at low temperature and far outperforming it at higher temperatures. Both CFR configurations performed significantly better than the batch setup in terms of temperature and yield, as was expected.

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Kapcsolatdinamikai folyamatelemzés processzometriával sine morbo és klinikai esetekben

Relationship dynamic process-analysis by processometry in sine morbo and clinical cases

Magyar Pszichológiai Szemle
Author: Bagdy Emőke

Célkitűzés: A processzometria módszerének alkalmazását bemutatni párok kapcsolatdinamikai folyamatainak követésében.

Módszer: A Közös Rorschach Vizsgálat (KRV) textusfeldolgozásának validált eljárása, amely a teszt jegyzőkönyv interakcióinak folyamatán át módot ad a páratlanul egyszeri kapcsolati viszonyminták „komputertomográfiás”, rétegeire bontott, finom elemzésére. A feldolgozás objektív módszertani oldala a számítógépes folyamatmonitorozás, a vizsgált három dimenzióban (dominancia, együttműködési aktivitás és intimitás), ötfokozatú skálán. Interpretatív elemzési oldala az üzenettartalmak szimbolikus jelentések mentén történőösszefűzése. A kommunikáció „hogyanja” és üzeneti tartalma („mit üzen” a v. sz.) együttesen a lelki mélységet bevilágító felismerésekhez segítenek hozzá.

Eredmények: A feldolgozott két esetet bemutató tanulmány, egy látszólag sine morbo pár „fallikus kol- lúziója”, valamint egy anorexia nervosában szenvedő lánynak édesanyjával való mély, lelki dinamikai azonossága arra nézve, hogy egy nőnek veszélyes felnőtté válnia. Titkos összejátszásuk közös nevezője: „maradjunk kislányok”.

Konklúzió: A tanulmány lehetőséget ad az elemzés lépéseinek és munkamódjának megismerésére. Rávilágít a KRV pár- és családdiagnosztikai jelentőségére a (rejtett) kapcsolatdinamikai történések megismerésében.

Objective: Introducing the application of processometry for the follow-up of relationship-dynamic processes of couples.

Method: The validated procedure of the Joint Rorschach Examination (JRE) text-elaboration that allows computer-tomographic, layered, precise analysis of unique, single relationship patterns through the process of test protocol interactions. The objective methodological side of elaboration is the computer-based process-monitoring in the three examined dimensions (dominance, collaboration activity and intimacy) on a five-point scale. The interpretative analytic side is linking contents of messages along symbolic meanings. The „how” of communication and content of its message („what does the subject communicate”) jointly contribute to recognition illuminating psychodynamic depth.

Results: the study of two adapted cases, the „phallic collusion” of an apparently sine morbo couple, and the deep, psychodynamic identity of a girl - suffering from anorexia nervosa - with her mother with regard to the fact that it is dangerous for a woman to become an adult. The common denominator of their secret collusion is ‘let’s stay girls’.

Conclusion: The study provides an opportunity to understand steps and working methods of the analysis. It highlights the couple and family diagnostic significance of JRE in the cognition of (hidden) relationship dynamic actions.

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The heat of reaction and kinetics of curing of diglycidyl ether of bisphenol-A (DGEBA) type of epoxy resin with catalytic amounts of ethylmethylimidazole (EMI) have been studied by differential power-compensated calorimetry as a part of the program for the study of process monitoring for composite materials. The results were compared with those from 1∶1 and 1∶2 molar mixtures of DGEBA and EMI. A method of determination of heat of reaction from dynamic thermoanalytical instruments was given according to basic thermodynamic principles. The complicated mechanism, possibly involving initial ionic formation, has also been observed in other measurements, such as by time-domain dielectric spectroscopy. The behavior of commercially available DGEBA resin versus purified monomeric DGEBA were compared. The melting point of purified monomeric DGEBA crystals is 41.4 °C with a heat of fusion of 81 J/g. The melt of DGEBA is difficult to crystallize upon cooling. The glass transition of purified DGEBA monomer occurs around −22 °C with aΔC p of 0.60 J/K/g.

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52 Newiadomiski J 2002: Seismogenic process monitoring, under publication Park J, Lindberg C R, Vernon F L 1987: J. Geophys. Res. , 92, 12675

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Reinikainen SP Louhi-Kultanen A Nystrom L . A study on batch cooling crystallization of sulphathiazole - process monitoring using

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